package ca.tatham.triplipse.wizards;

import org.eclipse.core.resources.IContainer;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.Path;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.window.Window;
import org.eclipse.jface.wizard.WizardPage;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Text;
import org.eclipse.ui.dialogs.ContainerSelectionDialog;

/**
 * Allows the user to create a new RDF file. Subclasses decide which type of RDF
 * file it is.
 * 
 * @author BenTatham
 */
class NewRdfWizardPage extends WizardPage {
	private final String m_fileExtension;

	private Text m_containerTextInput;
	private Text m_fileTextInput;
	private ISelection m_selection;

	public NewRdfWizardPage(ISelection selection, String fileExtension) {
		super("wizardPage");
		setTitle("RDF Editor");
		setDescription("This wizard opens or creates a new file with ."
				+ fileExtension + " extension.");
		this.m_selection = selection;
		this.m_fileExtension = fileExtension;
	}

	/**
	 * @see IDialogPage#createControl(Composite)
	 */
	public void createControl(Composite parent) {
		Composite container = new Composite(parent, SWT.NULL);
		GridLayout layout = new GridLayout();
		container.setLayout(layout);
		layout.numColumns = 3;
		layout.verticalSpacing = 9;
		Label label = new Label(container, SWT.NULL);
		label.setText("&Container:");

		m_containerTextInput = new Text(container, SWT.BORDER | SWT.SINGLE);
		GridData gd = new GridData(GridData.FILL_HORIZONTAL);
		m_containerTextInput.setLayoutData(gd);
		m_containerTextInput.addModifyListener(new ModifyListener() {
			public void modifyText(@SuppressWarnings("unused")
			ModifyEvent e) {
				dialogChanged();
			}
		});

		Button button = new Button(container, SWT.PUSH);
		button.setText("Browse...");
		button.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(@SuppressWarnings("unused")
			SelectionEvent e) {
				handleBrowse();
			}
		});
		label = new Label(container, SWT.NULL);
		label.setText("&File name:");

		m_fileTextInput = new Text(container, SWT.BORDER | SWT.SINGLE);
		gd = new GridData(GridData.FILL_HORIZONTAL);
		m_fileTextInput.setLayoutData(gd);
		m_fileTextInput.addModifyListener(new ModifyListener() {
			public void modifyText(@SuppressWarnings("unused")
			ModifyEvent e) {
				dialogChanged();
			}
		});
		initialize();
		dialogChanged();
		setControl(container);
	}

	/**
	 * Tests if the current workbench selection is a suitable container to use.
	 */

	private void initialize() {
		if (m_selection != null && m_selection.isEmpty() == false
				&& m_selection instanceof IStructuredSelection) {
			IStructuredSelection ssel = (IStructuredSelection) m_selection;
			if (ssel.size() > 1)
				return;
			Object obj = ssel.getFirstElement();
			if (obj instanceof IResource) {
				IContainer container;
				if (obj instanceof IContainer)
					container = (IContainer) obj;
				else
					container = ((IResource) obj).getParent();
				m_containerTextInput
						.setText(container.getFullPath().toString());
			}
		}
		m_fileTextInput.setText("new_file." + getFileExtension());
	}

	/**
	 * Uses the standard container selection dialog to choose the new value for
	 * the container field.
	 */

	void handleBrowse() {
		ContainerSelectionDialog dialog = new ContainerSelectionDialog(
				getShell(), ResourcesPlugin.getWorkspace().getRoot(), false,
				"Select new file container");
		if (dialog.open() == Window.OK) {
			Object[] result = dialog.getResult();
			if (result.length == 1) {
				m_containerTextInput.setText(((Path) result[0]).toString());
			}
		}
	}

	void dialogChanged() {
		IResource container = ResourcesPlugin.getWorkspace().getRoot()
				.findMember(new Path(getContainerName()));
		String fileName = getFileName();

		if (getContainerName().length() == 0) {
			updateStatus("File container must be specified");
			return;
		}
		if (container == null
				|| (container.getType() & (IResource.PROJECT | IResource.FOLDER)) == 0) {
			updateStatus("File container must exist");
			return;
		}
		if (!container.isAccessible()) {
			updateStatus("Project must be writable");
			return;
		}
		if (fileName.length() == 0) {
			updateStatus("File name must be specified");
			return;
		}
		if (fileName.replace('\\', '/').indexOf('/', 1) > 0) {
			updateStatus("File name must be valid");
			return;
		}
		int dotLoc = fileName.lastIndexOf('.');
		if (dotLoc != -1) {
			String ext = fileName.substring(dotLoc + 1);
			if (ext.equalsIgnoreCase(getFileExtension()) == false) {
				updateStatus("File extension must be \"" + getFileExtension()
						+ "\"");
				return;
			}
		}
		updateStatus(null);
	}

	private void updateStatus(String message) {
		setErrorMessage(message);
		setPageComplete(message == null);
	}

	public String getContainerName() {
		return m_containerTextInput.getText();
	}

	public String getFileName() {
		return m_fileTextInput.getText();
	}

	private String getFileExtension() {
		return m_fileExtension;
	}

}